high impedance analog pin

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Anonymous
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 Hi, Im giving variable analog input(max rating 5V) to PSoC 5lp in high impedance mode.Now my question is can I directly give the potentiometer input to PSoC?How much resistance does any analog pin provide in this mode? Will the current damage PSoC? 

   

Right now as precaution i have connected 1k in series with POT,Psoc is taking floating value when i switch the input near to zero volts.The reason being psoc is unable to detect ground because of that 1k ohm.

   

RISHI

   
        
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Anonymous
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        Hi upk   
Of course in Analog high Z mode,   
The input resistance should be exceed a few mega ohm, I guess.   
   
Instability around Vss is cause from rail-to-rail characteristic   
For example, acording to the ADC datasheet   
Analog input has characteristic such as shown in this picture,   
It's depending upon the setting.   
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ETRO_SSN583
Level 9
Level 9
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If the pot ranges outside Vdda, there is a spec on allowed injection

   

current into a pin to prevent latchup. Also a max current of 100 uA

   

thru input protection diode.

   

 

   

Regards, Dana.

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